Coaxial cable device



Oct. 21, 1947. A.-c. DAVIS C OAXIAL CABLE DEVICE Filed June 18, 1943WWWIIM INVENTOR Aer/402 6. .34 ms,

V ATTOR EY.

Patented Oct. 21, 1947 UNITED STATES PATENT OFFICE 11 Claims. 1

The invention relates to a co-axial cable device and to an arrangementfor switching a co-axial cable. The usual type of switch is notpractical for use with a co-axial cable, because instead of employing anelectrical conductor in its usual form, it embodies an outer tubularconductor and an inner co-axial conductor, as is well-known.

More particularly the invention relates to a coaxial switching deviceand has for an object to make it possible to select and connect in ordisconnect from the co-axial circuit any one of a number of co-axialunits. In its preferred form, such units are attenuator units, tofacilitate varying the impedance in the co-axial circuit.

Another object of the invention is to provide an attenuator unitsuitable for use in a co-axial cable circuit.

For further details of the invention, reference may be made to thedrawings wherein Fig. 1 is a plan View of a co-axial cable attenuatorunit according to the present invention.

Fig. 2 is an enlarged sectional view on line 2-2 of Fi 1.

Fig. .3 is a sectional view on line 33 of Fig. 2, locking in thedirection of the arrows.

Fig. 4 is a partial sectional view on line 4-4 of Fig. 2.

Fig. 5 is a longitudinal sectional View through one of the attenuatorunits with its associated contacts.

Referring to the drawings, the variable attenuator unit I of thisinvention is shown as connected between the co-axial cable terminals 2and 3. The unit I comprises a casing 4 having a handle 5 which may beoperated to select one of a number of attenuator units, and the value ofthe selected unit may be read at the window 6. The manner in which thisis accomplished will now be described.

I provide a number of attenuator units like the one shown at I in Fig.5, wherein the outer tubular conductor 8 is tapered at its opposite endsas indicated at 9 and III, and provided with an inner co-axial conductorH terminating in plugs I2 and I3. The co-axial conductor comprises oneor more series resistance elements, two being indicated at I4 and I5,and a shunt resistance element l6, one terminal of which is connected tothe co-axial conductor II, as indicated at IT, and the other terminalconnected to the tubular conductor 8, as indicated at I8. The co-axialconductor II is supported in the tubular conductor 8 by means of anumber of spaced insulating discs such as I9 and the plugs I2 and I3 aresupported ,by similar discs such as 20.

- A number of attenuator units like I are con- 7 structed, withdiiierent values of series and shunt resistances. The unit of Fig. 2 isshown as accommodating six such units of different attenuation values,although any other number may be used.

The left end of the attenuation unit I is adapted to be connected to asliding co-axial socket 26 having an outer conductor 2| which is slottedas indicated at 22 and tapered as indicated at 23 to fit the taper 9.Also, the inner conductor 24 is provided with a socket 25 to receive theplug I2. The inner conductor 24 is supported in the outer conductor 2|by discs like I 9 and 2H, not shown.

The right end of the unit I is similarly adapted to be connected to asimilar co-axial socket 26.

The outer conductor 42 of socket 26 is held in a sleeve 43 secured towall 3| by screws or the like 44.

The outer conductor 2| of socket 26 slides on the fixed split outerconductor 45 supported in sleeve 48 secured by screws 41 to the left endwall :48 of casing 4. Inner conductor 24 of socket 26 similarly slides,in or on the fixed inner conductor 49. Thus socket 26' may move back andforth along its axis While maintaining connection with the coaxial cable2. Inner conductor 49 is supported axially in fixed outer conductor 45by insulating discs 20. Also, inner conductor 24 is axiall supported inouter conductor 2!, and inner conductor 50 is axially supported in outerconductor 42, by insulating discs similar to I9, 20, 20', not shown.

The manner in which the attenuation units like I may be switched in andout of circuit with the terminals 2 and 3 will now be described inconnection with Figs. 2 to 4, wherein six attenuation units I, I, etc.are slidably mounted in two discs or plates 21 and 28 fixed to a shaft29 carried at its right end in a bearing 30 in the end wall 3| of casing4, and at its left end in a bearing 32 suitably supported from theinside of the front wall 33 of casing 4. The plate 28 has a circularflange 34 bearing indicia 35 which are readable through the window 6 toshow the attenuation value of the unit I connected in circuit. Each ofthe units like I is provided with a collar 31' to limit its slidingmovement to the left, it being urged in that direction by a compressionspring 38 around the right end of each tube like I, and

arranged between a collar 39 and the left face of the disc 28.

The units like I are held impositively against rotation by means of anotched disc 40 on the shaft 29, cooperating with a spring detent 4 I.

Shaft 29 has fixed thereto a gear 5|, with which a gear 52 fixed onshaft 53 is adapted to mesh when handle is pushed up. Shaft 53 canrotate and slide in the bearing 10. On the inner end of shaft 53 bears alever arm 54 pivoted at 55 and having an angular arm 56 pivotallyconnected at 51 to a, link 58 connected to a sliding detent 59 slidablymounted in an aperture 60 in the wall 6|. The detent 59 has acompression spring 62 which bears against the wall 6! and against acollar 63 to urge the detent 59 to the right. Detent 59 fits in any oneof a number of apertures such as 64, one of each of which is associatedwith each of the attenuation units 1 in such a manner as to align theselected unit 1 with sockets 26 and 26' when the detent 59 aligns withthe hole 64 belonging to that particular unit I.

The socket 26 has spaced collars 65 in which rides a fork 66 on the endof a lever 6'! pivoted at 68 to the wall 6!. Also lever 61 is pivotallyconnected to link 58 by a pin H so that movement of link 58 by handle 5will cause lever 61 to swing on its pivot 68.

Between the socket 46 and the collar 65 is arranged a compression spring69 to urge the socket 26' to the right. Spring 69 is strong enough tooverpower each of the springs like 38.

Fig. 2 shows one of the units 1 connected in circuit between the coaxialconductors 2 and 3. If it is desired to remove unit 1 from circuit andsubstitute another unit, the handle 5 is pushed in to mesh gears 51, 52and slide shaft 53 against lever 54 to retract the detent 59 from itsaperture 6d and to slide socket 26' to the left under action of pinconnection H. The length of the detent 59 is such that the shaft 29 isheld against rotation until socket 26' has been moved to the left farenough to disengage the left end of unit 7 and to permit the spring 38to disengage the right end of unit 1 from socket 26. In other words, theshaft 29 cannot be rotated until unit "I is disconnected at both of itsends. This insures that the shaft 29 will not be prematurely rotated anddamage the sockets 28 and 26'. After unit I is disengaged as abovedescribed, handle 5 is maintained pushed in and is rotated to bring thedesired new unit such as 1 into position between sockets 2B and 26, theinterlock between detent 59 and lever 67 preventing socket 26 frommoving to the right until detent 59 engages the aperture 54 associatedwith the new unit such as I. When detent 59 slides in its properaperture 64, the spring 59 slides socket 26 to the right to engage theleft end of unit I and to slide unit I in the discs 2'! and 28 againstthe action of spring 38, in order to connect the right end of unit I tothe socket 26. In this way, any of the attenuator units such as I can beinserted in the circuit between terminals 2 and 3, while preventingdamage to the sockets 26 and 26, as premature rotation of shaft 29 andpremature sliding movement of socket 26' are prevented by means of thedetent 29 and its associated parts.

It will be apparent that various modifications may be made in theinvention without departing from the spirit of the following claims. Forexample, for switching a micro wave circuit, the inner coaxial conductormay be omitted, and only the outer tubular conductor employed. Also oneor more of the above switching features may be used for switching typesof coaxial units other than the attenuation units herein disclosed.

I claim:

1. Relatively reciprocable coaxial contacts each having a tubular outerconductor and an inner coaxial conductor, a slidable coupling betweensaid inner conductors, a slidable coupling between said outerconductors, spring means tending to engage said couplings a carrier forsaid couplings, and a cooperating coupling registering device movable toone position to prevent engagement of said couplings when said couplingsare misaligned, said registering device being movable to anotherposition to lock said carrier and permit said spring means to engagesaid couplings when the latter are aligned, a drive member movable intoand out of driving relation with said carrier, and an operativeconnection between said registering device and said drive member forunlocking said carrier on movement of said drive member into drivingrelation with said carrier.

2. A coaxial cable unit comprising a pair of spaced coaxial cablecontacts, one fixed and one movable, means supporting said movablecontact for reciprocating movement, a movable carrier, a lurality ofcoaxial cable devices having coaxial cable contacts, each of saiddevices being slidably mounted on said carrier, means supporting saidcarrier for movement to bring any one of said devices into operativerelation with said first contacts, and means for reciprocating saidmovable contact into connection with a selected one of said carriercontacts to slide the selected said device into connection with saidfixed contact.

3. An attenuator unit comprising a pair of spaced coaxial cablecontacts, a movable carrier, a plurality of coaxial cable pad units onsaid carrier, means supporting said carrier for movement to bring anyone of said pad units in line with said contacts, means for axiallymoving one of said contacts in one direction to connect the selected padunit to both of said contacts, and means operative to move the selectedone of said pad units axially in the other direction and therebydisconnect one end of the selected pad unit from one of said contactswhen said axially movable means disconnects the other contact from theother end of the selected pad unit.

l. An attenuator unit comprising a base, spaced aligned coaxial cablecontacts on said base, a. carrier on said base, a plurality of coaxialcable attenuation elements on said carrier, means supporting saidcarrier for movement to align said elements one at a time with saidspaced contacts, an operating member movable into and out of driverelation with said carrier, and means operated by movement of saidoperating member between driving and non-driving relations for movingthe selected element into connection with or disconnection from both ofsaid spaced contacts, and means controlled by movement of said operatingmember from one relation to the other on locking and unlocking saidcarrier.

5. A coaxial cable unit having spaced cable contacts, one of which isslidable, a carrier, a coaxial cable element on said carrier, a drivemember for said carrier, said drive member having a drive position andan idle position, means operable to lock or unlock said carrier and toconnect or disconnect said slidable contact and said element uponoperation of said drive member from one of said positions to the other.

6. A unit according to claim 5 comprising means for automaticallydisconnecting said element from said other contact upon disconnection ofsaid slidable contact from said element.

7. A coaxial cable device comprising a relatively fixed coaxial cablecontact and an axially slidable coaxial cable contact, a plurality ofslidable coaxial cable units therefor, a carrier for said units,operating means comprising a handle movable to one position, when saidcarrier is stationary, to

slide said slidable contact into engagement with one end of a selectedone of said units and thereby connect the other end of the selected unitto said fixed contact, said handle being movable to another positionwhen said carrier is stationary, to operate said operating means andslide said slidable contact out of engagement with its respective end ofthe selected unit and disconnect the other end of the selected unit fromsaid fixed contact.

8. A coaxial cable device having spaced coaxial cable contacts, one ofwhich is slidable, a rotatable carrier, a plurality of coaxial cableelements on said carrier, means rotatably supporting said carrier foraligning said cable elements in sequence with said spaced contacts, arotatable and slidable drive member for said carrier, said drive memberhaving a drive position and an idle position, means operable to locksaid carrier when each of said cable elements is aligned with saidspaced contacts, spring means urging said lock means to lock position,means operated by sliding movement of said drive member to driveposition for unlocking said lock means, means operated by slidingmovement of said drive member for connecting or disconnecting saidslidable contact and the selected element, and means operated byrotation of said drive member, when in drive position, for rotating saidcarrier.

9. A tubular conductor device comprising spaced tubular contacts, aplurality of tubular contact units, a rotatable carrier for said units,means supporting said carrier to align said units one at a time withsaid spaced contacts, operating means for connecting or disconnectingany one of said units between said spaced contacts when said carrier isstationary, a drive member for rotating said carrier, and means undercontrol of said drive member for preventing rotation of said carrieruntil said spaced contacts are disconnected from the associated unit.

10. A tubular conductor device comprising a tubular terminal contact, aplurality of tubular conductor units therefor, a telescoping member onsaid terminal contact and a cooperating telescoping member on each ofsaid units, a carrier for said units, a drive member movable into andout of driving relation with said carrier, spring means for telescopingsaid terminal contact with any one of said units, and means operated bymovement of said drive member into driving relation with said carrier toovercome said spring and separate said terminal contact from itsassociated unit.

11. A tubular conductor device comprising a pair of spaced tubularcontacts, one fixed and one movable, means supporting said movablecontact for reciprocating movement, a movable carrier, a plurality ofdevices each having tubular contacts, each of said devices beingslidably mounted on said carrier, means supporting said carrier formovement to bring any one of said devices into alignment with saidspaced contacts, means for reciprocating said movable contact intotelescoping connection with a selected one of said carrier contacts toslide the selected said device into telescoping connection with saidfixed contact, and spring means for each of said devices for maintainingall idle devices out of the path of said fixed contact and for slidingthe selected device out of contact with said fixed contact on separationof said movable contact from the selected device.

ARTHUR C. DAVIS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 851,266 Walloch Apr. 23, 19071,905,353 Potter Apr. 25, 1933 1,929,878 Clavier Oct. 10, 1933 1,957,538Jensen May 8, 1934 2,209,152 Daniels July 23, 1940 2,116,983 Schultz May10, 1938 2,233,166 Hahn Feb. 25, 1941 2,255,898 Robb Sept. 16, 1941FOREIGN PATENTS Number Country Date 110,494 Australia Apr. 30, 1940

